The present invention relates to fluid regulators and in particular to fluid regulators for use in the delivery of medical fluids.
Fluid regulators are known in the medical area for the delivery of a medical gas, such as oxygen, to a patient. Exemplary fluid regulators are capable of providing multiple calibrated flow rates from a source of pressurized fluid to a cannula or other device for output to a patient.
In an exemplary embodiment, a fluid regulator is provided. The fluid regulator comprising a cylindrical body including a first portion configured to be coupled to a source of high pressure fluid and a second portion configured to be coupled to a cannula. The first portion including a fluid inlet and the second portion including a fluid outlet in fluid communication with the fluid inlet. The cylindrical body having an open end and a reduced diameter portion adjacent the open end. The fluid regulator further comprising a flow restrictor having at least a first fluid passage configured to provide a first restricted flow rate of fluid and a second fluid passage configured to provide a second restricted flow rate of fluid. The flow restrictor being received in the open end of the cylindrical body portion and moveable relative to the body portion so that one of the first fluid passage and the second fluid passage is selectively interposed between the fluid inlet of the body and the fluid outlet of the body to restrict the flow rate of fluid from the fluid inlet of the body to the fluid outlet of the body. The fluid regulator further comprising a flow selector coupled to the flow restrictor and positioned adjacent the open end of the cylindrical body portion. The flow selector including a first portion having a diameter larger than a diameter of the reduced diameter portion of the cylindrical body. In one example, a longitudinal extent of the reduced diameter portion of the cylindrical body is about 7 percent of an overall length of the cylindrical body. In another example, a longitudinal extent of the reduced diameter portion of the cylindrical body is about 0.25 inches. In a further example, the reduced diameter portion of the cylindrical body includes a window positioned so that a portion of a second portion of the flow selector is visible therethrough, the second portion of the flow selector being positioned within the open end of the cylindrical body, the visible portion of the second portion of the flow selector including an indicia indicating a flow rate of the one of the first fluid passage and the second fluid passage is selectively interposed between the fluid inlet of the body and the fluid outlet of the body. In still a further example, the cylindrical body includes a first diameter larger than the reduced diameter portion and the diameter of the first portion of the flow selector is substantially equal to the first diameter of the cylindrical body. In yet a further example, the fluid regulator further comprises a pressure reduction section being received in the open end of the body and positioned between the fluid inlet of the body and the flow restrictor, the pressure reduction section being configured to receive fluid at a first pressure from the fluid inlet and to provide fluid at a lower pressure to the flow restrictor; and a housing positioned within the open end of the body, the housing including a recess into which the flow selector and the pressure reduction section are positioned and a fluid conduit which is aligned with the fluid outlet of the body and selectively aligned with a respective fluid passage of the flow restrictor. In a variation, the housing is coupled to the body with a coupler which extends into the housing from an exterior of the body.
In another exemplary embodiment, a fluid regulator is provided. The fluid regulator comprising a body having an interior cavity accessible through an open end, a fluid inlet which is configured to receive a high pressure fluid from a source of pressurized fluid, and a fluid outlet. The fluid regulator further comprising a housing positioned in the interior cavity of the body. The housing including an interior cavity accessible from an open end of the housing, a fluid inlet accessible through the open end of the housing which is in fluid communication with the fluid inlet of the body and a fluid outlet in fluid communication with the fluid inlet of the housing and the fluid outlet of the body. The fluid regulator further comprising a pressure reduction section positioned within the interior cavity of the housing through the open end of the housing, the pressure reduction section being configured to receive the high pressure fluid from the fluid inlet of the body and to provide a lower pressure fluid to the fluid inlet of the housing. The pressure reduction section including: a base member including a base portion and a guide portion extending from the base portion, the base member having a central passageway extending there through, the central passageway being positioned such that it is in fluid communication with the fluid inlet of the body; a piston including a piston base portion and a stem portion, the stem portion being configured to be received by the central passageway in the guide portion of the base member, the piston having a fluid passageway there through with a fluid inlet in the stem portion and a fluid outlet in the piston base portion, the fluid outlet being in fluid communication with the fluid inlet of the housing; and a biasing member sized to receive the guide portion of the base member, a first end of the biasing member being positioned adjacent the base portion of the base member and a second end of the biasing member being positioned adjacent a seat surface of the piston base portion, the seat surface being located in a recess formed in the piston base portion, the recess being sized to receive a first end of the guide portion of the base member. The fluid regulator further comprising a rotatable flow restrictor including a flow control portion disposed within the interior cavity of the housing and a stem portion coupled to the disk portion and extending through an aperture connecting the cavity of the housing and a second end of the housing, the flow control portion including a plurality of fluid conduits each selectively being brought into fluid communication with the fluid conduit of the housing through the rotation of the flow restrictor relative to the housing. In an example, the flow control portion of the flow restrictor includes a first axial surface containing the respective fluid outlets for each of the plurality of fluid conduits of the flow restrictor, a second axial surface including the respective fluid inlets for each of the plurality of fluid conduits of the flow restrictor, and a radial surface disposed between the first axial surface and the second axial surface, the radial surface including openings sized to receive respective occluders which are advanced into the respective fluid conduit to reduce a cross-sectional area of the respective fluid conduit of the flow restrictor. In another example, the flow control portion of the flow restrictor includes a first axial surface including the respective fluid outlets for each of the plurality of fluid conduits of the flow restrictor, a second axial surface including the respective fluid inlets for each of the plurality of fluid conduits of the flow restrictor, and a radial surface disposed between the first axial surface and the second axial surface, the radial surface including openings sized to receive respective occluders which are advanced into the respective fluid conduit to reduce a cross-sectional area of the respective fluid conduit of the flow restrictor. In a further example, the flow control portion of the flow restrictor includes a first axial surface including the respective fluid inlets for each of the plurality of fluid conduits of the flow restrictor, a second axial surface including openings sized to receive respective occluders which are advanced into the respective fluid conduit to reduce a cross-sectional area of the respective fluid conduit of the flow restrictor, and a radial surface disposed between the first axial surface and the second axial surface including the respective fluid outlets for each of the plurality of fluid conduits of the flow restrictor. In still a further example, the body is generally cylindrical having a first diameter and a reduced diameter portion, the reduced diameter portion being adjacent the open end. In a variation, the fluid regulator further comprises a flow selector coupled to the flow restrictor, the flow restrictor being positioned adjacent the open end of the cylindrical body such that a first portion of the flow selector is received in the open end of the cylindrical body and a second portion of the flow selector extends beyond the open end of the cylindrical body, the second portion of the flow selector having a diameter larger than the diameter of the reduced diameter portion. In yet a further example, the fluid regulator further comprises a hose barb which is coupled to the fluid outlet of the body and extends into the housing. In a variation the hose barb restrain the rotational movement of the housing relative to the body. In yet still a further example, the longitudinal movement of the housing within the open end of the body is limited by a coupler which is received within a recess of the interior cavity of the body, the coupler contacting a top portion of the housing. In yet still another example, the housing is coupled to the body with a coupler which extends into the housing from an exterior of the body.
In a further exemplary embodiment, a method of reducing the pressure of a fluid introduced through a fluid inlet of a body of a fluid regulator, the fluid inlet being located in an interior cavity of the body accessible through an open end of the body of the fluid regulator is provided. The method comprising the steps of: positioning a housing having an interior cavity accessible through an open end and a fluid conduit, the interior cavity having a stop surface, the fluid conduit having a fluid inlet in an axial surface of the interior cavity and a fluid outlet in an external radial surface of the housing; coupling a flow restrictor having a plurality of fluid conduits each having a respective flow rate, the flow restrictor being rotatable relative to the housing to permit each fluid conduit to be selectively brought into fluid communication with the fluid conduit of the housing through the rotation of the flow restrictor relative to the housing; positioning a pressure reduction section between the fluid inlet and the flow restrictor, the pressure reduction section including a base member, a piston, and a biasing member. The base member includes a base portion and a guide portion extending from the base portion, the base member having a central passageway extending there through, the central passageway being positioned such that it is in fluid communication with the fluid inlet of the body. The piston includes a piston base portion and a stem portion, the stem portion being configured to be received by the central passageway in the guide portion of the base member, the piston having a fluid passageway there through with a fluid inlet in the stem portion and a fluid outlet in the piston base portion, the fluid outlet being in fluid communication with the flow restrictor. The biasing member sized to receive the guide portion of the base member, a first end of the biasing member being positioned adjacent the base portion of the base member and a second end of the biasing member being positioned adjacent a seat surface of the piston base portion. The seat surface being located in a recess of the piston base portion. The recess being sized to receive a first end of the guide portion of the base member. The method further comprising the steps of positioning the pressure reduction section in the interior cavity of the housing, a rear side of the piston of the pressure reduction section being positioned adjacent the stop surface of the interior cavity of the housing; positioning the housing in the interior cavity of the body; coupling the housing to the body; passing fluid from the fluid inlet of the body through the central passageway of the guide portion of the base member into a fluid conduit of the piston which includes a transverse conduit in the stem portion of the piston in fluid communication with the central passageway of the base member and a longitudinal conduit in the stem portion of the piston in fluid communication with the transverse conduit of the stem portion and a rear side of the piston resulting in an increase in the fluid pressure adjacent the rear side of the piston in a space between the piston and the flow restrictor; permitting the movement of the piston in a direction away from the flow restrictor as the pressure in the space increases, the stem portion of the piston being further advanced into the guide portion of the base member; and receiving the guide portion of the base member in the recess of the piston as the piston moves in the direction away from the flow restrictor. In an example, the flow restrictor is rotated to a position wherein fluid is prevented from entering the fluid inlet of the housing resulting in the pressure of fluid in the space between the piston and the flow restrictor increasing and the piston moving further in the direction away from the flow restrictor until a seal coupled to an end of the stem portion contacts the fluid inlet of the body. In another example, the step of coupling the housing to the body includes the steps of: coupling a hose barb to the fluid outlet of the body; and extending a portion of hose barb into the fluid outlet of the housing. In a variation the step of coupling the housing to the body further includes the step of locating a retainer in a recess of the interior cavity of the body, the retainer contacting a top portion of the housing.